/**
 * @file
 * Ethernet Interface Skeleton
 *
 */

/*
 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
 * All rights reserved. 
 * 
 * Redistribution and use in source and binary forms, with or without modification, 
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 * 
 * Author: Adam Dunkels <adam@sics.se>
 *
 */

/*
 * This file is a skeleton for developing Ethernet network interface
 * drivers for lwIP. Add code to the low_level functions and do a
 * search-and-replace for the word "ethernetif" to replace it with
 * something that better describes your network interface.
 */

#include "config.h" // MakingThings - network system conditionalization
#ifdef MAKE_CTRL_NETWORK

#include "lwip/opt.h"

/* This is all reimplemented by FreeRTOS/MakingThings */
#if 1 /* don't build, this is only a skeleton, see previous comment */

#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/pbuf.h"
#include "lwip/sys.h"
#include <lwip/stats.h>
#include <lwip/snmp.h>
#include "netif/etharp.h"
#include "netif/ppp_oe.h"

/* MAKINGTHINGS: Addition for FreeRTOS */
#include "FreeRTOS.h"
#include "SAM7_EMAC.h"
#include "Emac.h"

/* MAKINGTHINGS: Addition for FreeRTOS */
#define netifMTU							( 1500 )
#define netifINTERFACE_TASK_STACK_SIZE		( 150 )
#define netifINTERFACE_TASK_PRIORITY		( configMAX_PRIORITIES - 1 )
#define netifGUARD_BLOCK_TIME				( 250 )

/* Define those to better describe your network interface. */
#define IFNAME0 'e'
#define IFNAME1 'n'

/**
 * Helper struct to hold private data used to operate your ethernet interface.
 * Keeping the ethernet address of the MAC in this struct is not necessary
 * as it is already kept in the struct netif.
 * But this is only an example, anyway...
 */
struct ethernetif {
  struct eth_addr *ethaddr;
  /* Add whatever per-interface state that is needed here. */
};

/* MAKINGTHINGS: Add */
//static const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
static struct netif *xNetIf = NULL;    

/* Forward declarations. */
//static void  ethernetif_input(struct netif *netif);
static void  ethernetif_input(void *); // MakingThings
// err_t ethernetif_init( struct netif *netif ); // MakingThings

/**
 * In this function, the hardware should be initialized.
 * Called from ethernetif_init().
 *
 * @param netif the already initialized lwip network interface structure
 *        for this ethernetif
 */
static void
low_level_init(struct netif *netif)
{
  //struct ethernetif *ethernetif = netif->state;
  /* MAKINGTHINGS: Addition for FREERTOS */
  unsigned portBASE_TYPE uxPriority;

  /* set MAC hardware address length */
  netif->hwaddr_len = ETHARP_HWADDR_LEN;

  /* set MAC hardware address */
  /* MAKINGTHINGS: Added/Tweaked */
  netif->hwaddr[0] = emacETHADDR0;
  netif->hwaddr[1] = emacETHADDR1;
  netif->hwaddr[2] = emacETHADDR2;
  netif->hwaddr[3] = emacETHADDR3;
  netif->hwaddr[4] = emacETHADDR4;
  netif->hwaddr[5] = emacETHADDR5;
  
  /* MAKINGTHINGS: Added */
  netif->mtu = netifMTU;
  
  /* MAKINGTHINGS: Removed */
  /* maximum transfer unit */
  //netif->mtu = 1500;
  
  /* device capabilities */
  /* don't set NETIF_FLAG_ETHARP if this device is not an ethernet one */
  netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP;
 
  /* Do whatever else is needed to initialize interface. */
  xNetIf = netif;

  /* FreeRTOS: Initialise the EMAC.  This routine contains code that polls status bits.  
  If the Ethernet cable is not plugged in then this can take a considerable 
  time.  To prevent this starving lower priority tasks of processing time we
  lower our priority prior to the call, then raise it back again once the
  initialisation is complete. */
  uxPriority = uxTaskPriorityGet( NULL );
  vTaskPrioritySet( NULL, tskIDLE_PRIORITY );
  while( xEMACInit() == NULL )
  {
    __asm( "NOP" );
  }
  vTaskPrioritySet( NULL, uxPriority );

  /* Create the task that handles the EMAC. */
  xTaskCreate( ethernetif_input, ( signed portCHAR * ) "ETH_INT", netifINTERFACE_TASK_STACK_SIZE, NULL, netifINTERFACE_TASK_PRIORITY, NULL );
}

/**
 * This function should do the actual transmission of the packet. The packet is
 * contained in the pbuf that is passed to the function. This pbuf
 * might be chained.
 *
 * @param netif the lwip network interface structure for this ethernetif
 * @param p the MAC packet to send (e.g. IP packet including MAC addresses and type)
 * @return ERR_OK if the packet could be sent
 *         an err_t value if the packet couldn't be sent
 *
 * @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to
 *       strange results. You might consider waiting for space in the DMA queue
 *       to become availale since the stack doesn't retry to send a packet
 *       dropped because of memory failure (except for the TCP timers).
 */

static err_t
low_level_output(struct netif *netif, struct pbuf *p)
{
  (void)netif; // MakingThings
  //struct ethernetif *ethernetif = netif->state;
  struct pbuf *q;

  /* MAKINGTHINGS: add */
  static xSemaphoreHandle xTxSemaphore = NULL;
  err_t xReturn = ERR_OK;
  
  /* MAKINGTHINGS: initiate transfer(); */
  if( xTxSemaphore == NULL )
  {
    vSemaphoreCreateBinary( xTxSemaphore );
  }
  //initiate transfer();
  
#if ETH_PAD_SIZE
  pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
#endif
  
  /* MAKINGTHINGS: Remove */
  /*
  for(q = p; q != NULL; q = q->next) {
    * Send the data from the pbuf to the interface, one pbuf at a
       time. The size of the data in each pbuf is kept in the ->len
       variable. *
    send data from(q->payload, q->len);
  }
  

  signal that packet should be sent();
  */

  /* MAKINGTHINGS: Add */
  /* Access to the EMAC is guarded using a semaphore. */
  if( xSemaphoreTake( xTxSemaphore, netifGUARD_BLOCK_TIME ) )
  {
    for( q = p; q != NULL; q = q->next )
    {
      /* Send the data from the pbuf to the interface, one pbuf at a 
      time. The size of the data in each pbuf is kept in the ->len 
      variable.  if q->next == NULL then this is the last pbuf in the
      chain. */
      if( !lEMACSend( q->payload, q->len, ( q->next == NULL ) ) )
      {
        xReturn = ~ERR_OK;
      }
    }
    xSemaphoreGive( xTxSemaphore );
  }

#if ETH_PAD_SIZE
  pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
#endif
  
  LINK_STATS_INC(link.xmit);

  /* MakingThings: Remove */
  // return ERR_OK;

  /* MakingThings: Add */
  return xReturn;
}

/**
 * Should allocate a pbuf and transfer the bytes of the incoming
 * packet from the interface into the pbuf.
 *
 * @param netif the lwip network interface structure for this ethernetif
 * @return a pbuf filled with the received packet (including MAC header)
 *         NULL on memory error
 */
static struct pbuf *
low_level_input(struct netif *netif)
{
  //struct ethernetif *ethernetif = netif->state;
  /* MakingThings:  Initialized p */
  struct pbuf *p = NULL;
  struct pbuf *q;
  /* MakingThings:  Initialized len */
  u16_t len = 0;

  /* MakingThings: Add for FreeRTOS */
  static xSemaphoreHandle xRxSemaphore = NULL;

  /* Parameter not used. */
  ( void ) netif;

  /* MakingThings: Add for FreeRTOS */
  if( xRxSemaphore == NULL )
  {
    vSemaphoreCreateBinary( xRxSemaphore );
  }

  /* Access to the emac is guarded using a semaphore. */
  if( xSemaphoreTake( xRxSemaphore, netifGUARD_BLOCK_TIME ) )
  {
    /* Obtain the size of the packet. */
    len = ulEMACInputLength();

		if( len )
		{

#if ETH_PAD_SIZE
  len += ETH_PAD_SIZE; /* allow room for Ethernet padding */
#endif

  /* We allocate a pbuf chain of pbufs from the pool. */
  p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);
  
  if (p != NULL) {

#if ETH_PAD_SIZE
    pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
#endif

    /* MakingThings: Added */
    /* Let the driver know we are going to read a new packet. */
    vEMACRead( NULL, 0, len );

    /* We iterate over the pbuf chain until we have read the entire
     * packet into the pbuf. */
    for(q = p; q != NULL; q = q->next) {
      /* Read enough bytes to fill this pbuf in the chain. The
       * available data in the pbuf is given by the q->len
       * variable. */
      // read data into(q->payload, q->len);
      vEMACRead( q->payload, q->len, len );
    }
    // MakingThings: for FreeRTOS - nope
        // acknowledge that packet has been read();

#if ETH_PAD_SIZE
    pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
#endif

    LINK_STATS_INC(link.recv);
  } else {
    //drop packet();
    LINK_STATS_INC(link.memerr);
    LINK_STATS_INC(link.drop);
  }
  }
    xSemaphoreGive( xRxSemaphore );
  }

  return p;  
}

/**
 * This function should be called when a packet is ready to be read
 * from the interface. It uses the function low_level_input() that
 * should handle the actual reception of bytes from the network
 * interface. Then the type of the received packet is determined and
 * the appropriate input function is called.
 *
 * @param netif the lwip network interface structure for this ethernetif
 */
static void
ethernetif_input( void* notused )
//ethernetif_input(struct netif *netif)
{
  (void)notused; // MakingThings 
  struct ethernetif *ethernetif;
  struct eth_hdr *ethhdr;
  struct pbuf *p;
  for( ;; )
  {
    do
    {
      // ethernetif = netif->state;
      ethernetif = xNetIf->state; // MakingThings

      /* move received packet into a new pbuf */
      p = low_level_input(xNetIf); // MakingThings
      /* no packet could be read, silently ignore this */
      // if (p == NULL) return; // MakingThings
      if( p == NULL )
      {
        /* No packet could be read.  Wait a for an interrupt to tell us 
        there is more data available. */
        vEMACWaitForInput();
      }
    } while( p == NULL );

    /* points to packet payload, which starts with an Ethernet header */
    ethhdr = p->payload;

    switch (htons(ethhdr->type)) {
    /* IP or ARP packet? */
      case ETHTYPE_IP:
      case ETHTYPE_ARP:
#if PPPOE_SUPPORT
  /* PPPoE packet? */
      case ETHTYPE_PPPOEDISC:
      case ETHTYPE_PPPOE:
#endif /* PPPOE_SUPPORT */
    /* full packet send to tcpip_thread to process */
      //if (netif->input(p, netif)!=ERR_OK)
      if (xNetIf->input(p, xNetIf)!=ERR_OK)
      { LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n"));
        pbuf_free(p);
        p = NULL;
      }
      break;

    default:
      pbuf_free(p);
      p = NULL;
      break;
    }
  }
}

/**
 * Should be called at the beginning of the program to set up the
 * network interface. It calls the function low_level_init() to do the
 * actual setup of the hardware.
 *
 * This function should be passed as a parameter to netif_add().
 *
 * @param netif the lwip network interface structure for this ethernetif
 * @return ERR_OK if the loopif is initialized
 *         ERR_MEM if private data couldn't be allocated
 *         any other err_t on error
 */
err_t
ethernetif_init(struct netif *netif)
{
  struct ethernetif *ethernetif;

  LWIP_ASSERT("netif != NULL", (netif != NULL));
    
  ethernetif = mem_malloc(sizeof(struct ethernetif));
  if (ethernetif == NULL) {
    LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_init: out of memory\n"));
    return ERR_MEM;
  }

#if LWIP_NETIF_HOSTNAME
  /* Initialize interface hostname */
  netif->hostname = "lwip";
#endif /* LWIP_NETIF_HOSTNAME */

  /*
   * Initialize the snmp variables and counters inside the struct netif.
   * The last argument should be replaced with your link speed, in units
   * of bits per second.
   */
  NETIF_INIT_SNMP(netif, snmp_ifType_ethernet_csmacd, 1000000);

  netif->state = ethernetif;
  netif->name[0] = IFNAME0;
  netif->name[1] = IFNAME1;
  /* We directly use etharp_output() here to save a function call.
   * You can instead declare your own function an call etharp_output()
   * from it if you have to do some checks before sending (e.g. if link
   * is available...) */
  netif->output = etharp_output;
  netif->linkoutput = low_level_output;
  
  ethernetif->ethaddr = (struct eth_addr *)&(netif->hwaddr[0]);
  
  /* initialize the hardware */
  low_level_init(netif);

  return ERR_OK;
}

#endif /* 0 */

#endif // MAKE_CTRL_NETWORK

